Pulverizing apparatus



Dec. 14 ,1926.

1,610,345 w. c. WILLIAMS PULVERIZING APPARATUS Filed April 10, 1922 2 Sheets-Shet 1 I'ufenIg;

' Deco 9 w. c. WILLIAMS PULVERIZING APPARATUS Filed April 10, 1922 2 Sheets-Sheet 2 K W z M W. m n. O 1 HQ NB QAJ NA /IN n E M H mm Q m Jib! \W m 7 MN 0 M a a a o a I M W HQ JH .1 .f I M1] lkhfllrlwwtnll I .H a 0 o o a 0 I o 1 xx .w\ A ,.i \kw 1 hi Q mm it has. reached Patented Dec. 14, 1 926.

UNITED STATES PATENT OFFICE.

WISTER C. WILLIAMS, DECATUR, ILLINOIS, ASSIGNOR TO MCLAUGHLIN COAL RE- DUGTION COMPANY, OF DECATUR, ILLINOIS, A CORPORATION OF SOUTH DAKOTA.

PULVERIZING APPARATUS.

Application filed April 10, 1922. Serial No. 551,012.

This invention relates to improvements in pulverizing apparatus and more particularly to the removal of. the pulverized material from the pulverizing machine after a predetermined degree of fineness.

In certain types of pulverizing machines the pulverized material is removed continuously during the operation of the apparatus by withdrawing the same in suspension in an air current, the theory being that only those particles which are sufiiciently fine will be carried off in a current of air having a certain velocity. It has been found, however, that in order to prevent the withdrawal of particles which are not sufliciently fine, the movement of material or the velocity of the current of air carrying the particles in suspension must be so slow that much of the material possessing a suflicient degree of fineness'is left behind. This results in a reduction of the capacity and efliciency of such machines and apparatus.

The primary object of this invention is to provide a method of and apparatus for increasing the capacity and efficiency of a pulverizing machine of thistype.

The invention consists in the novel combinations, constructions and arrangements for carrying out the above stated objects and such other objects as may appear from the following specification and claims.

The invention is illustrated in a preferred embodiment in the accompanying drawings wherein: f

Fig. 1 is a view somewhat diagrammatic in form of the apparatus showing in eleva tion a form of pulverizing machine.

Fig. 2 is a longitudinal vertical section of a type of pulverizing machine shown in Fig. 1.

Fig. :3 is a transverse section taken along the l1ne 3-3 of Fig. 2, and I Fig. 4 is a fra mentary detailed view of the air-blast nozz es. T v

Like characters ofreference indicate like parts in the several figures ofthe drawings.

The construction herein shown, while particularly adapted for use in pulverizing fuel, may be employed for pulverizin -other material susceptible of pulverization in this type of apparatus. or the purposes of illustration I have shown a pulverizing machine designated generally as 10'and which will be described more in detail hereinafter. Referring particularly to Fig. 1, the material to be pulverized is fed from the chute or other conveying-means 11 into the receiving hopper 12 from which it is carried into the interior of the pulverizer. Within the pulverizer are means for suspending in the air therein the finest articles of material without materially dlsturbing the material which is undergoing the process of pulverization. These fine particles together with such other coarser particles as may be suspended in the air are withdrawn from the interior of the pulverizer through a pipe 13 connected to the intake side of a blower or fan 14 which creates suflieient suction in the interior of the pulverizer to withdraw the suspended particles. I

I The suspended particles are passed through the blower and into a cyclone separator 15 through the pipe 16. The cyclone separator is of any Well known type and is adapted by reason ofthe centrifugal force of the whirling air and particles to separate the the hopper 17 at the base of the separator.

Such coarser particles preferably pass di rectly through the spout 18 and into the receiving hopper 12 and from thence enter the pulverizer to be subjected to further pul verization.

The particles of pulverized material of the required degree of fineness remain suspended in the air and are withdrawn from the cyclone separator through the pipe 19 by means of the blower or .fan 20. By means of the control of the suction exerted by the blower 20, an additional control is had of the separation of the fine from the coarser particles within the separator 15. The current of air carrying the fine particles is passed through the pipe 21 into any suitable form of separator 22 adapted to remove the fine articles from the air. For the purpose of i lustration I have shown a separator having the sides thereof formed of fabric 23 whose mesh is sufliciently fine to prevent the escape of the fine pulverized material while permitting the escape of thevair. The pulverized 'materialft hen falls into the storage hopper 24 from which it may be withdrawn through the spout 25.

The particular form of collector 22 forms no part of my invention and may be of any suitable type capable of depositing the pulverized material so that it may be collected.

' elements consisting of cylindrical rollers, 27

which extend the length of the drum and are preferably of a multiplicity of different diameters. Pulverization is effected by the which action is increased by the employment of rollers of different diameters. In

order to insure relative movement of the rollers during the rotation of the drum small cleats 28 are secured to the interior of the drum in order to cause displacement of the rollers during rotation of the drum.

The drum is centered on supports 29 and provided with bearing rings 30 by means of which the drum, is revolubly supported upon the rollers 31 which are grooved to correspond with the rings 30. The'rollers are rotated by the worm and gear 32 and 33 through the shaft 34, the rotation of which causes the rotation of the drum. I

The material 'to'be treated is supplied to the hopper 12 from which itpasses through the conduit 35 to the cylindrical casing36,

supported at opposite ends upon the supports 29. The supports 29 are provided with rings 37 and set screws 38 for holding the casing 36 centrally relative to the pulverizing drum.

Arranged within the casing 36 is a screw conveyor 39 the shaft 40 of which extends through the caps 41 which close the opposite ends of the casing 36, the shaft being provided at one end with a driving pulley 42.

In order to distribute the material evenly lengthwise of the drum, the casing 36 is formed with a helical delivery edge or slot 43, the high point of which is at the end of the casing into which the material is delivered and the low point near the other end of the casing. At the discharge end of the v drum is arranged a housing 44 from which leads the pipe 13 running to the suction fan 14.

For the purpose of initially suspending the fine material so that the same gnay be drawn by suction by the fan 14, compressed air is supplied to the pipe 45 leading into the housing 44 and connected with the horizontal pipe 46 having inclined air nozzles 47. \The jets of air escaping through the nozzles 47 are directed obliquelv to the body I that certain particles of material not suficiently fine are also suspended in the air in the drum. Such suspended particles are withdrawn in the manner stated above by a suction of air sutficient only to withdraw the suspended particles and not strong I enough to interfere with the bulk of mate abrasive action of the rollers on one another rial in the drum which is not pulverized sufiiciently fine. But in order to accomplish efficient operation and'to increase the capacverizationin'the manner before described.

By regulating the velocity of the air jets through the nozzles 47, and the suction produced by the fans 14 and 20 it is possible to not only vary the degree of fineness of the finished product but to regulate the operation ofthe apparatus so that the process of withdrawing the fine material removes as small a percentage as possible of the coarser particles which are to be returned for further pulverizationconsistent with efficient operation.

Instead of returning the coarser particles to the pulverizer for further treatment this material may be withdrawn from the apparatus and marketed as sea coal for use in foundries. The product is of very considerable value in this connection on account of the uniformity in size .of the particles. It is free from extremely fine powder present in most sea coals and which is detrinental to the product when used in moldmg.

I claim:

1. A pulverizing and sizing, system including feed mechanism, pulverizing mechanism, means for creating suction through said pulverizing mechanism, a separator in to which said suction means delivers its air current, a second suction means beyond said separator in the direction of 'air travel, a second separator into which said second suction means delivers its air current, and means for returning material from said first sepain combinatiom'a pulverizer, feeding means therefor, a closed air conduit leading from terla by an air blast, means independent of said agitating means for creatmg air current in said conduit for withdrawing particles of material from said pulverizer, a

separator into which said air currents are dlrected, a second suction means in said cirouit beyond said separator, and a screening device into which said second means delivers said alr current wherein the particles of 10 matter may be removed from said current. andcollected and means for. delivering the material from said 'first separator to said pulverizer for further treatment.

WISTER c; WILLIAMS. 

